The present invention relates to a double molding process. More particularly, the invention relates to a double molding process whereby at least one sign is produced on a product comprising an inner core and an outer cover while said product is molded.
It is well known that many companies need to affix visual information on the products they sell so that customers can readily have access to this information. This visual information may be in the form of names, words, numbers, logos, trademarks, or any other type of symbols conveying information.
It is common practice to display such information by means of labels secured to the products or by simply printing the information onto the products. However, very often, the labels are deteriorated or become detached and the prints fade out after a while. Furthermore, this additional step of having to label a product after it has been manufactured constitutes additional costs.
Therefore, it would be very useful to provide a molding process which is capable of producing a sign on a product while said product is molded, the sign lasting all throughout the working life of the product.
U.S. Pat. No. 5,711,721 granted on Jan. 27, 1998 to Brenda JOHNSON et al describes a ferrule for golf clubs. This ferrule is made from a first layer having a raised part and from a second layer molded onto the first layer so as to surround the raised part. This raised part has a different color from that of the second layer and can thus fulfill certain functions, such as displaying a logo or a drawing, or indicating a club number.
U.S. Pat. No. 5,604,006 granted on Feb. 18, 1997 to James A. PONCHAUD et al describes a molding process for making a label bearing article. This process consists of fixing a label by means of an adhesive onto an exterior surface of a thin thermoplastic substrate. The substrate and the affixed label are then placed in a mold cavity of an injection molding device, with the exterior surface bearing the affixed label placed against the wall of the mold cavity. Then, the mold cavity is injected with a molten thermoplastic resin at high pressure which forces the exterior surface of the substrate and the affixed label to be pressed against the wall of the mold cavity, resulting in the affixed label being recessed into the exterior surface and consequently molding the substrate to the label to thus form the label bearing article.
U.S. Pat. No. 5,726,029 granted on May 26, 1998 to Nakamichi et al describes a molding process for producing a molded product containing another molded product. The process consists of initially forming in a first mold a first molded product having interlocking projections and holes. This first molded product is then transferred into a second mold having interlocking grooves and pins and is securely positioned therein by the interlocking of the grooves and pins with the corresponding projections and holes. A molding material is then injected into the second mold so as to form a second molded product containing the first molded product.
Also known to the applicants are the following U.S. patents which describe different processes and apparatuses for producing insignia bearing molded products: U.S. Pat. Nos. 5,673,503; 5,783,133; 5,794,768; and 5,814,252.
None of the above-mentioned patents discloses or suggests a molding process which is capable of producing a sign on a product while said product is molded, said sign lasting, all throughout the working life of the product.
The object of the present invention is to provide a double molding process which satisfies each of the above mentioned needs.
More particularly, the object of the invention is to provide a double molding process for producing a sign on a product while said product is molded, said sign lasting all throughout the working life of the product by virtue of its construction.
In accordance with the invention, the above object is achieved by a double molding process whereby at least one sign is produced on a product comprising an inner core and an outer cover while said product is molded, said process comprising the steps of:
(a) molding the inner core with a first molding material, said inner core having at least one side provided with at least one groove in the shape of said at least one sign and at least one other side provided with at least one channel leading within the inner core to said at least one groove; and
(b) molding the outer cover onto the inner core with a second molding material in such a manner that said at least one side of said inner core is not covered by the second molding material and thus remains visible, and said at least one channel of said at least one other side and said at least one groove of said a least one side are both filled un with said second molding material to produce said at least one sign on said at least one side of the product.